1393] NOTES AND COMMENTS 70 



Synthetic Protoplasm 



PrOFESSOK Hkkkkka also sent us a letter containing an account of 

 some experiments he has made on what he calls a ' synthetic proto- 

 plasm ' made by him by mixing pepsine, peptone, acetic fibrine, oleic 

 acid, soap, sugar, extract of bile, carbonate of soda, lime, and of 

 ammonia, lactate of lime, phosphates of lime and magnesium, sulphates 

 of lime and iron, and chloride of sodium. When this compound is 

 placed in water and examined under the microscope, violent diffusion 

 currents are set up, and streaming movements of a very active kind 

 last for a few minutes. When this is over, the addition of a trace 

 of liquid ammonia renews the activity, which lasts for several hours. 

 These movements he rightly attributes to the liberation of gases by 

 the particles of the compound, and he compares with this the 

 liberation of carbonic oxide by living protoplasm, suggesting that in 

 the discharge of that gas lies the secret of the streaming movements 

 of protoplasm. Professor Herrera was good enough to send us a 

 small quantity of his compound, and on this we have successfully 

 repeated some of the experiments he describes. The little mass was 

 particularly active in water with a trace of ammonia : diffusion 

 currents, movements of the whole mass, and the protrusion of 

 pseudopodia-like processes occurred. We found, however, that the 

 resemblance to protoplasm was destroyed from the fact that the 

 mass did not retain its coherence ; small masses were constantly 

 discharged from its surface, and it seemed to melt away in a com- 

 paratively short time. In this respect it compared unfavourably 

 with Biitschli's foams, and we imagine that, although Dr Herrera 

 has imitated with considerable success the very complicated chemical 

 composition and consequent instability of protoplasm, he has not 

 been so successful with its structure. On the other hand, it is 

 possible that the substance, in its postal journey from Mexico, 

 has deteriorated. We think that he has begun a most ingenious line 

 of experiment, and wish him all success in his further attempts. 



The Phyto-Planktox of the Atlantic 



On May 12, Mr George Murray and Mr V. H. Blackmail presented 

 to the Eoyal Society their observations on a year's work in collect- 

 ing phyto-plankton along a track from the Channel to Panama, 

 carried out by Captains Milner and Rudge, and also during one 

 voyage to Brazil by Captain Tindall. They also gave the results 

 of their own observations on living material at sea. The material 

 was obtained by the pumping method described in our June number 

 (vol. xii., p. 367). 



One of the objects of the authors' work was to determine, if 

 possible, the nature of the microscopic and little understood objects 

 known as coccospheres and rhabdospheres. In the present paper 



